1-Bromo-4-butylbenzene stands out as a brominated aromatic compound used often as a raw material across fine chemical, pharmaceutical, and materials manufacturing sectors. This chemical features a butyl group tethered to the para-position of a benzene ring, with a bromine atom attached at the first carbon. The structure and reactivity draw consistent interest from researchers and process engineers aiming for precision and reliability in their downstream chemistry. I’ve worked with intermediate aromatic bromides before—they underpin synthesis steps leading to more complicated targets, so handling and purity often shape the outcome of whole production campaigns.
Looking at the structure, 1-Bromo-4-butylbenzene has a benzene core which provides aromatic stability. The molecular formula is C10H13Br, and its molecular weight sits around 213.12 g/mol. The molecule has a four-carbon butyl chain attached to the benzene ring, giving it extra hydrophobic character compared to simpler halo-benzenes. In a lab, this molecule’s size and shape mean it isn’t volatile or especially light, so measures like fume-hood use and careful transfer become necessary.
This compound arrives most commonly as a colorless to pale yellow liquid under standard conditions. The bromo and butyl groups give it a higher density than water, and its density clocks in around 1.178 grams per cubic centimeter at 25°C. I have encountered it in both liquid and solidified forms, depending on storage temperature; with a melting point close to -24°C and a boiling point near 255°C, it’s typically handled as a somewhat oily liquid in liter-sized or drum containers. Crystalline or powdered versions are unusual, mostly because of the molecule's melting characteristics, but cooling does produce some flake-like or pearly solid material.
1-Bromo-4-butylbenzene reacts with a range of chemical reagents—those working with Grignard or palladium-catalyzed cross-coupling methods will recognize its utility. The aromatic ring resists most air and moisture effects, though bromine does make it a moderate electrophile. Safety data sheets highlight risks: ingestion, skin absorption, and inhalation may cause harm. It doesn’t ignite sharply but should stay away from direct heat sources. The chemical’s stability allows storage for longer periods, yet standard precautions—goggles, gloves, good ventilation—are mandatory. From personal experience, a small spill leaves an unmistakable odor and a slick residue, which underscores the need for absorbent and chemical-resistant surfaces.
High-purity material usually lands above 98% assay by GC or NMR. Water content and related impurities, like 4-butylphenol or dibutylbenzene, receive tight controls in production. Each drum or bottle uses a harmonized system (HS) Code of 2903.69, placing it in the family of halogenated derivatives of aromatic hydrocarbons for customs and transportation tracing. Suppliers label the containers with both CAS and batch data to assist in compliance and traceability. These records matter, especially for traceability or regulatory auditing in pharmaceutical companies or chemical producers.
As a building block, 1-Bromo-4-butylbenzene shines in organic synthesis pipelines—forming new carbon–carbon bonds, or introducing the butyl tail to new frameworks. Anyone working with this type of material understands the risk isn’t just in handling but also storage and disposal. Its stability reduces accident frequency, but once it enters waste streams, authorities expect careful tracking because brominated aromatics can persist in the environment. Industrial sites manage these chemicals by closed-system transfers, automated solution dispensing, and regularly updated hazard protocols. In my experience, planning a workspace layout and designing workflow steps that isolate or contain spills simplifies emergency action and reduces health risk.
Switching to alternative packaging, using secondary containment, and employing digital inventory management helps sites keep tighter control. Training teams to spot exposure signs, building clear response plans, and investing in ongoing personal protective equipment upgrades go a long way toward making workplaces safer. Substituting less hazardous substances can be difficult in specialty synthesis—the unique reactivity makes this compound hard to replace—yet supporting research into greener alternatives remains an active area. My own labs have benefited from standardized handling kits and spill-absorbent pads dedicated to halogenated organics, which limit downtime after an incident and prevent environmental release.
